wood rot?!

[Missdjcabz]

Hey all! Im a FTB and our valuation for our mortgage was done thursday, im super excited so rang the bank today to find out if they had it back, they said it hadnt been finalised yet but could tell us there were signs of damp and wood rot!! Im now stressing that is going to affect the valuation.
We knew there was damp as there is a wet mark on an upstairs wall (see attached pic) and the roof tiles above this area have been replaced, the house has been unoccupied for around 9months but there is no mould or further damp so assumed it was all sorted.
Is this something i should be worried about?
Im a proper stress head and know nothing about houses really, thanks in advance for any help xx

You need a proper survey, not just the mortgage company's valuation

we had a home buyers report done at the same time, we should have the results in the next few days, we decided against a full structural survey as the house is ex housing association and they are brilliant around here with making sure properties are spot on, and before that they were military, the housing association replaced all windows and doors, central heating, fuse box, guttering and any loose roof tiles before putting the house up for sale and they are even still cutting the grass which is nice of them.
but the wood rot thing has stressed me out, im worried our mortgage company will say they wont lend us the money we need for the purchase based on that and i wont get my new home